Not enough government subsidy.
If anything the government should stop giving people money and instead open more public schools. That’d increase competition (ie supply) rather than demand and thus lower prices.
Imagine if every private school would have to compete against a well funded and cheap (relatively) public option. That’d have an immediate impact on driving down prices across the board.
Demand side government involvement is always a bad idea. It universally leads to poor outcomes and profit capture by the wrong institutions. Either supply side or no side is my vote.
Most of the countries which people usually talk about here - France, Germany, Spain, etc. - have significantly lower matriculation and graduation rates than the US does.
I've studied CS 3.5 years for ~550€ per year (around $700). This includes free public transportation, but excludes an apartment.
In Germany, you can get a gov. funded student loan which can go up to ~750€ per Month. You have to pay back only the half of that. The 750€/Month is the highest amount that you can get. But you get it only if you have to pay the health insurance yourself, which is ~90€/Month. Otherwise, the maximum amount ~650€/Month. What you can get depends on the income of your parents. If your parents earn a lot of money, you get less.
What you have to pay back is capped to 10000€ in total, free of interest. So if you get more than 20000€ in total, you still have to pay back only 10000€. You even get a discount on that if you pay back early. If you are taking this loan, your maximum debt is 10000€ (to be repaid only after the receiver exceeds a certain income level after graduation).
You don't get it forever, though. It is limited to 3-5 years, depending on what you study.
It is called Bafög: https://en.m.wikipedia.org/wiki/Bundesausbildungsförderungsg...
https://en.m.wikipedia.org/wiki/Student_financial_aid_(Germa...
I'd consider this as "free enough".